Your API can pass in Virginia and fail in Singapore
Assert runs checks from six regions. When one of them fails an assertion, Assert re-runs the check in the others before it pages anyone.
One region fails. Assert asks the other five.
A single failed check is often the network between one probe and your origin. Assert does not page on it. It re-runs the check in the other five regions, counts the verdicts, and opens one incident when the failure is real.
- The other regions re-run the same check within seconds.
- The incident records which regions agreed and which did not.
- Each region measures latency against its own budget.
- Your plan includes the regions, and Assert never charges per check.
The other five passed. Assert sent no page.
Six cities, five continents
The free plan runs from one region, Starter and Pro from three, and Team from all six. The list itself does not change.
Failures that only one region sees
CDN misconfiguration
An edge node serving stale content answers fast and answers wrong. Only the region behind that node sees it.
DNS propagation
During a migration the old record survives in some resolvers for hours. The regions still pointing at the old host fail first.
Regional outages
A cloud provider loses one region. Your primary region is fine, so single-region monitoring reports nothing.
Latency budgets
A p95 that passes in Virginia can miss by 400ms in Singapore. Assert holds each region to its own budget.
SLA evidence
Show an international customer the latency their region actually measured, per check, for the last 90 days.
Load balancer routing
Geographic routing sends a region to the wrong origin. The response is valid, and it comes from the wrong continent.
